I am looking for a tach and have seen the 3 at Tower. The Tower, The GloBee IntelliTach, and the Hobbico. Anyone using one of these? I do not want to spend more that $30 USD. I am in no need of one that is accurate to 1-3 RPM's, just need one to give me a good reading and be constant.

I saw this quote about the GloBee: "Because of its sensitivity, this does not know whether it is looking at a propeller or an incandescent or fluorescent light, which typically strobes at 60 cycles per second or 3600 cycles per minute. When set for 2-blades it will read 360 or 3600, 3-blades: 240 or 2400 and 4-blades: 180 or 1800. This is a quick way to test the calibration. In direct sunlight this will read zero when turned ON."

Do all these units have a way to calibrate from a know source?

I am leaning towards the GloBee, let me know please.


Thanks,
Fred

All of the optical tachs will "read" a light bulb the same.

the globee is a great tach...

anyway, you can also calibrate from your monitor. check your refresh rate, and then just bring up a white screen and hold the tach to it. technically though you can't calibrate them since you can't change settings, and they shouldn't need it anyway, they are just pulse counters.